Let-off for looms



Patented Oct. 12, 1926.

UNITED STATES -1,603,074 ATENT OFFICE.

CARL EGGART, OF ARBON,'SWITZERLAND, ASSIGNOR TO SbCIETE ANONYME ADOLPHE SAURER, OF ARBOR, SWITZERLAND, A. CORPORATION OF SWITZERLAND.

LET-OFF ron LOOMS.

Application filed September13, 1924, Serial No. 737,494, and in Switzerland April 24, 1924.

This invention has for its object to provide improved means for regulating the tension of the warp as it unwinds from the warp-beam. In accordance with the inven- P 6 tion the warp-beam besides being rotated from the drivlng mechanism of the loom under normal conditions, is made movable bodily away from the shed, under the control of suitable tension devices, for the purpose of taking up excessive slack or restoring the proper tension and is movable again toward theshed under the influence of the restored tension. The invention will be more fully explained hereinafter with reference to the accompanying drawing in which it is illustrated and in which Figure 1 is a view in side elevation of one embodiment of the invention.

Figure 2 is a similar view showing another embodiment of the invention.

In the embodiment of the invention shown in Figure 1, the .warp-beam 1, which itself 'may be of ordinaryor suitable construction,

is mounted upon a support 2 which in thisinstance is arranged to slide upon the frame 3 toward and from the shed of the loom, guide rails 4 being provided on the frame.

The warp-beam has fixed thereto a worm wheel 5 which is engaged by a worm 6 on a shaft 7 which is mounted for rotation in suitable bearings on the support 2. At one -end the shaft 7 is provided with a hand wheel 8 for manual operation when desired and at the other end is provided with means through which it may be operatively connected with. the drivingmechanism of the loom. In the arrangement shown the shaft 7 carries a friction disc 9 for co-operation with a corresponding friction disc 10 on. an

aligned shaft 11- drivenfrom any convenient and suitable part of the loom/mechanism. A tension device is provided the action of -which tends to move the frame 2 and the warp-beam 1 bodily in a direction away 415 from the shed of the loom, thereby placing and maintaining the warp under tension, the rotation of the warp-beam by the tension on the-warp being prevented by the engagement of the worm gear 5 with the worm 6.

the embodiment of the invention .illustrated in Figure 1 the tension device comprises a cord 12 which is passed over a guide pulley 13 and is connected to a lever 14 pivoted on the frame 3 and carrying a weight 15 which is slidable on the lever for the purpose of warp-beam and of the extent to which the adjusting the tension. The warp is shown as passing from the Warp-beam over a guide roller 16. i 4

' In the embodiment of the invention shown in Figure 2 the warp-beam is mounted as before in a support 2 and has a worm wheel 5 engaged by a worm 6 on the operating shaft 7, but in this instance the support 2, instead of being arranged to slide on the frame 3, is carried by levers 27 and 28 which 66 are pivoted on the frame 3 and permit the support to have rectilinear movement toward and from the shed of the loom. In this instance the lever 28 is formed as a bell crank lever. the longer arm of which is engaged by a spring 29, connected at its other end to the frame 3, the tendency of which is, as before, to move the warp-beam away from the shed.

In operation, under normal conditions, that is, at normal tension of the warp, the warp-beam is rotated from the driving mechanism of the loom through the shaft 7 and worm gears 6 and 5, to unwind the warp as it is taken up in the progress of the weaving. Should the tension of the warp be relaxed from any cause, as, for example, by being unwound too rapidly, thetension device acts simultaneously with the relaxing of the tension on the warp to move the warp beam is'a direction away from the shed-of the loom and thereby to maintain the proper tension, as determined by adjustment of the tension device, upon the warp regardless of the position of the warp has been unwound. Through such movement of the warp-beam with its support and the shaft 7 in the particular arrangement shown in both Figures 1. and 2, the friction disc 9 is moved out of operative relation with the driving disc 10 and the rotation of the Warp-beam from the driving mechanism of the loom ceases. When the tension of the warp has been restored to normal the action of-the tension device may be overcome and the warp-beam moved again to its initial position with the friction disc 9 in driving engagement with In the disc 10.

thereby such devices as have been found necessary heretofore to counteract, the effeclis of such changes may be dispensed wit 1.

It will be understood that various changes may be made in details of construction and arrangement and that, except as pointed out in the claims, the invention is not restricted to the particular constructions shown and described herein.

I claim as my invention:

1. In a constant tension let-off the combination of a Warp'beam, means to rotate the same to unwind the Warp, devices to prevent rotation thereof, a support for the warpbeam movable to place the warp-beam in and out of operative relation With said means, and a tension device tending normally to move the support in a direction to place the warp-beam out of operative relation with said means.

2. In a constant tension let-off the combination of a warp-beam, means to rotate the same to unwind the warp, devices to prevent rotation thereof a support for the Warp-beam movable to place the warp-beam in and out of operative relation with said means, said means and devices being carried by the support, and a tension device tending normally to move the support in a direction to place the warp-beam out of operative relation with said means.

3. In a constant tension let-off the combination of a warp-beam, a support therefor, movable toward and from the shed of the loom, a worm gear on the warp-beam, a shaft mounted on the support and having a worm in en agement with the worm gear of the warpeam, driving means for said shaft into and out of operative relation with which it is movable with said support, and a tension device tending normally to move the support in a direction away from the shed of the-loom.

4. In a constant tension let-off the comfor movable toward and from the shed of the loom, a worm gear on the Warp-beam, a shaft mounted on the support and having a worm in engagement withthe worm gear of the warp-beam and a friction disc, a driving shaft 1n alignment with the first mentioned shaft and having a friction disc for co-operation with the friction disc of the first mentioned shaft and into and out of operative relation with which the friction disc of the first mentioned shaft is moved with said support, and a tension device tending normally to move the support in a direction away from the shed of the loom.

5. In a constant tension let-off the combination of a warp-beam, a support therefor movable toward and from the shed of the loom, means to support said support for rectilinear movement with respect to the shed, means for rotating the warp-beam, a tension device tending normally to move the support in a direction away from the shed of the loom todisengage said rotation means, and devices to prevent rotation of the Warpbeam when sald rotation means are disengaged.

6. In a constant tension let-off the combination of a warp-beam, a support therefor movable toward and from the shed of the loom, a tension device tending normally to move the support in a direction away from the shed of-the loom, means for rotating the warp-beam including two separable members, one of which is movable with the warp-beam into and out of operative relation with the other, and devices to prevent rotation of the warp-beam When said members are out of operative relation.

This specification signed this 2 day of September A. D. 1924.

CARL EGGART. 

